It is a common practice to use a coupler to secure a conduit to an enclosure. Often, the conduit is an electrical conduit and the enclosure is an electrical enclosure such as a junction box. The electrical conduit can be used to facilitate routing electrical wire in and out of the electrical enclosure. In certain examples, the electrical closure can be an explosion-proof enclosure.
A typical coupler can include a hub and a lock nut adapted to mount on the hub. The hub can form a hollow sleeve having a first end portion with internal threads and a second end portion with external threads. The hub can also include a flange positioned between the first and second end portions. In use, the coupler is mounted at an opening defined through a wall of an enclosure. The hub is mounted outside the enclosure with the second end portion of the hub extending through the enclosure opening and the flange opposing the wall of the enclosure. A seal can be compressed between the flange and the wall of the enclosure to provide environmental sealing. The lock nut is positioned inside the enclosure and is threaded on the second end portion of the hub to lock the hub in place at the enclosure opening. A conduit such as an electrical conduit can be threaded within the first end portion of the hub to attach the conduit to the coupler. In certain examples, the lock nut can include one or more ground connection locations for connecting a ground wire to the coupler to provide grounding of the conduit and/or the enclosure. Example patents that disclose conduit couplers include U.S. Pat. No. 3,104,120 and U.S. Pat. No. 5,374,785.
Ease of installation is an important consideration for conduit couplers. Hence features that allow a technician to efficiently install and ground a conduit coupler at a given location are desirable.